Even if you don’t get that sick from the flu, aside from missing school or work there is the very real problem that influenza is very contagious — and you can be contagious before you realize that you have the flu. That means you can spread it to others, some of whom may get very sick. Getting immunized helps keep everyone safe: it’s not just about you, it’s about everyone around you. This is especially true for children, who aren’t always great about washing their hands and tend to touch lots of things and people around them.

Here are a few things all parents should know about the flu vaccine:

1. It’s the best way to prevent the flu. Hand washing is crucial, and staying away from sick people helps, but we can’t wash our hands every second, and we can’t always know who is sick. It’s true that the vaccine isn’t 100% effective (the effectiveness varies by year) but it’s your best bet if you don’t want to get sick.

2. You and your children should get it early. The flu season runs from roughly September to March. The sooner you get it, the sooner you are protected. It’s best to get it done before the end of October. This is especially true if your child is young and hasn’t had it before, because…

4. People with egg allergy can get the flu shot. If the allergy is severe you should talk to your doctor, as in those cases it’s recommended that people be monitored and have medications to treat an allergic reaction at the ready, but it’s unlikely that that anything will happen.

5. There are very few people who shouldn’t get a flu shot. Children less than six months old or who had a definite allergic reaction to the flu shot are the only ones who can’t. Those with a history of Guillain-Barre Syndrome should talk to their doctor, but that’s rare. If a child is significantly ill we will sometimes postpone the shot, but children with a minor illness like a cold can get it.

6. There are some people who really need a flu shot. That includes babies, who are at higher risk of complications, as well as children with asthma, other lung diseases, heart problems, weakened immune systems, or other chronic illnesses. You should call your doctor right away about getting vaccinated if your child falls into one of these groups.

7. There’s no more nasal spray version. Sorry. It didn’t work very well. That means a needle for everyone. But there are lots of ways to ease the pain of the needle, so talk to your doctor.

8. You don’t need to worry about thimerosal. Thimerosal is a preservative that has been used to prevent contamination in vaccines. Some people have worried that it could be linked to autism, but it has been studied carefully and there is no actual evidence that this is true. There is no thimerosal in the vaccines we routinely give to children. There are some formulations of the flu vaccine that contain a tiny amount of thimerosal, but there are also preservative-free formulations available. Either way, your child is safe. Talk to your doctor if you have questions about this.

9. You can’t catch the flu from the flu vaccine. The virus in the vaccine is inactivated. As with any vaccine, there can be side effects; the most common ones are pain at the injection site or fever. But it cannot give you the flu.

10. In many states, older children can get the flu shot at their local pharmacy. We pediatricians like you to get shots at our office, so that we have a record of it and can answer any questions. But we mostly want your child to be vaccinated, and we understand that getting to the office isn’t always easy. Check with your local public health department to see what your options are. If your child does get the flu shot at a pharmacy or flu clinic, please bring documentation to your doctor so that they can put it in their medical record.

If you have any questions about the flu or the flu shot, check out flu.gov.